JP4935686B2 - Knee airbag device with column - Google Patents

Description

  The present invention relates to a column-attached knee airbag device.

The structure which provided the knee airbag apparatus for restraining a passenger | crew's knee part in the column cover which covers a steering column is disclosed (refer patent document 1 and patent document 2). Further, a structure is disclosed in which a steering column moves downward in the axial direction and absorbs an impact during a frontal collision of a vehicle (see Patent Document 1).
JP 2007-133102 A JP 2007-203937 A

  Incidentally, the steering column is generally provided with a steering lock device (hereinafter simply referred to as “lock device”) combined with a key cylinder and an ignition switch. However, in the above-described conventional example, no consideration is given to such a locking device.

  In consideration of the above fact, the present invention suppresses the interference between the column cover and the lock device when the knee air bag is deployed and the steering column is contracted to absorb the shock, thereby absorbing the shock of the steering column. The purpose is to secure the stroke.

  The invention of claim 1 is configured to be retractable by a load input of a predetermined value or more, and is fixed to a lower side of a steering column in which a lock device is fixed to a fixed side portion at the time of contraction. A knee airbag module in which a knee airbag that can be inflated and deployed to the room side is folded and stored, and covers a rear end side of the steering column including the knee airbag module and the lock device, and is movable when the steering column is contracted A column cover having an airbag door that is fixed to a side portion and that is deployed to a vehicle compartment side by the inflation pressure of the knee airbag, and when the knee airbag is deployed, the locking device is included in the column cover. The lock cover part to cover is comprised so that it may detach | leave from a normal position.

  In the knee-attached airbag device according to the first aspect, gas is supplied to the folded knee airbag at the time of a frontal collision, and the knee airbag starts to expand and deploy. When the inflation pressure of the knee airbag acts on the column cover, the airbag door provided on the column cover is deployed to the vehicle compartment side. At this time, the lock cover portion that covers the lock device of the column cover is detached from the normal position. The knee airbag is inflated and deployed toward the passenger compartment through an opening formed by the deployment of the airbag door and the lock cover.

  On the other hand, when a load greater than or equal to a predetermined value is input to the steering column, the steering column contracts to absorb shock. At this time, the column cover strokes relative to the fixed side portion of the steering column to which the locking device is fixed together with the movable side portion of the steering column. Here, as described above, since the lock cover portion of the column cover is detached from the normal position, interference between the column cover and the lock device is suppressed when the steering column is contracted. Thereby, the shock absorption stroke of the steering column can be ensured.

  According to a second aspect of the present invention, in the column-attached knee airbag device according to the first aspect, the column cover extends in a vehicle width direction along a rear edge of the airbag door and a rear edge of the lock cover portion. A planned lateral rupture portion and a longitudinal rupture planned portion extending in the vehicle front-rear direction between the airbag door and the lock cover portion are set, and when the knee airbag is deployed, the airbag door is deployed downward in the vehicle. And the said lock cover part is comprised so that it may expand | deploy in a vehicle width direction, It is characterized by the above-mentioned.

  In the knee-attached airbag device with the column according to the second aspect, when the inflation pressure of the knee airbag acts on the column cover, the laterally fractured scheduled portion and the longitudinally fractured scheduled portion set in the column cover are fractured. As a result, the airbag door is deployed downward in the vehicle, and the lock cover portion is deployed in the vehicle width direction. That is, the lock cover part is detached from the normal position. The knee airbag is inflated and deployed toward the passenger compartment through an opening formed by the deployment of the airbag door and the lock cover.

  On the other hand, when the steering column contracts to absorb the shock, the column cover strokes relative to the fixed side portion of the steering column to which the lock device is fixed, together with the movable side portion of the steering column. Here, as described above, since the lock cover portion of the column cover is detached from the normal position, interference between the column cover and the lock device is suppressed when the steering column is contracted. In this way, in the knee-attached airbag device with the column according to claim 2, the impact of the steering column is absorbed by the laterally scheduled and longitudinally fractured portions being broken and the airbag door and the lock cover portion being deployed. Stroke can be secured.

  According to a third aspect of the present invention, in the column-attached knee airbag device according to the first aspect, the column cover has a divided structure including an upper cover on the upper side of the vehicle and a lower cover on the lower side of the vehicle. A split structure having a rear cover portion located on the rear side and a front cover portion located on the vehicle front side and configured to include the lock cover portion is formed, and the front cover portion is provided when the knee airbag is deployed. It is characterized in that it can be deployed to the passenger compartment side.

  In the knee-attached airbag device according to the third aspect, when the inflation pressure of the knee airbag acts on the lower cover of the column cover, the front cover portion including the lock cover portion of the lower cover is deployed toward the vehicle compartment side. That is, the lock cover part is detached from the normal position. The knee airbag is inflated and deployed toward the passenger compartment through an opening formed by the deployment of the front cover portion.

  On the other hand, when the steering column contracts to absorb the shock, the column cover strokes relative to the fixed side portion of the steering column to which the lock device is fixed, together with the movable side portion of the steering column. Here, as described above, since the lock cover portion of the column cover is detached from the normal position, interference between the column cover and the lock device is suppressed when the steering column is contracted. As described above, in the column-attached knee airbag device according to the third aspect, the shock absorbing stroke of the steering column can be ensured by deploying the front cover portion including the lock cover portion.

  According to a fourth aspect of the present invention, in the column-attached knee airbag device according to the third aspect, a cut extending in the vehicle front-rear direction is set at corners on both sides in the vehicle width direction at the rear end portion of the front cover portion. It is characterized by being.

  In the knee-attached knee airbag device according to claim 4, since the cuts extending in the vehicle front-rear direction are set at the corners on both sides in the vehicle width direction at the rear end portion of the front cover portion, the inflation pressure of the knee airbag is set. When the column cover acts on the lower cover of the column cover, the lower wall portion located between the cuts in the lower cover becomes an airbag door and expands downward in the vehicle, and the lock cover portion on the vehicle upper side from the cut extends in the vehicle width direction. To do. By setting a cut in the lower cover, the airbag door and the lock cover can be easily deployed when the knee airbag is deployed.

  According to a fifth aspect of the present invention, in the column-attached knee airbag device according to the first aspect, the airbag door is separately assembled to a lower portion of the column cover, and the column cover is provided via an extendable hinge. And is configured to be able to deploy to the vehicle compartment side in a state of being detached from the column cover by the inflation pressure of the knee airbag and supported by the hinge.

  In the knee-attached airbag device according to claim 5, when the inflation pressure of the knee airbag acts on the column cover, the airbag door assembled separately at the lower portion of the column cover is detached from the column cover. Then, it is deployed to the passenger compartment side while being supported by the hinge.

  On the other hand, when the steering column contracts to absorb the impact, the column cover strokes relative to the stationary side portion of the steering column, to which the locking device is fixed, together with the movable side portion of the steering column. Enter the instrument panel while leaving the bag door on the passenger compartment side. At this time, the hinge connecting the airbag door and the column cover extends, so that interference between the airbag door and the instrument panel can be suppressed. For this reason, in the knee-attached airbag device according to the fifth aspect, the shock absorbing stroke of the steering column can be secured by suppressing the interference between the instrument panel and the airbag door.

  According to a sixth aspect of the present invention, in the column-attached knee airbag device according to the first aspect, the airbag door is formed to wrap around from the lower wall portion of the column cover to the side wall portion so as to include the lock cover portion. A front door portion that can be deployed centered on a hinge portion on the front side of the vehicle when the knee airbag is deployed, and a vehicle rear side of the front door portion. And a rear door portion that can be developed centering on the hinge portion on the side.

  In the knee-attached airbag device according to claim 6, when the inflation pressure of the knee airbag acts on the column cover, the front door portion of the airbag door is deployed around the hinge portion on the front side of the vehicle, and the airbag The rear door portion of the bag door develops around the hinge portion on the vehicle rear side. Since the front door portion is formed to wrap around from the lower wall portion of the column cover to the side wall portion so as to include the lock cover portion, the lock cover portion is detached from the normal position when the front door portion is deployed. . The knee airbag is inflated and deployed toward the vehicle compartment through an opening formed by the development of the front door portion and the rear door portion.

  On the other hand, when the steering column contracts to absorb the shock, the column cover strokes relative to the fixed side portion of the steering column to which the lock device is fixed, together with the movable side portion of the steering column. Here, as described above, since the lock cover portion of the column cover is detached from the normal position, interference between the column cover and the lock device is suppressed when the steering column is contracted. Thus, in the column-attached knee airbag device according to the sixth aspect, the front door portion including the lock cover portion is deployed, so that the shock absorbing stroke of the steering column can be ensured.

  According to a seventh aspect of the present invention, in the column-attached knee airbag device according to any one of the first to sixth aspects, the side wall portion of the column cover located behind the lock device in the column cover includes the It is characterized in that a fragile portion that is weak against the axial load of the steering column is provided.

  In the knee-attached airbag device with a column according to claim 7, even if the side wall of the column cover interferes with the lock device when the column cover strokes as the steering column contracts, the column cover is provided on the side wall. The weakened part which deform | transforms can deform | transform more easily, and the interference can be suppressed. Thereby, the shock absorption stroke of the steering column can be ensured.

  As described above, according to the column-attached knee airbag device according to the first aspect of the present invention, when the knee airbag is deployed and the steering column is contracted to absorb the impact, the column cover and the lock are locked. It is possible to obtain an excellent effect of suppressing the interference with the apparatus and ensuring the shock absorbing stroke of the steering column.

  According to the knee-attached airbag device with the column according to claim 2, the impact-absorbing stroke of the steering column is reduced by breaking the planned lateral breakage portion and the longitudinal breakage planned portion and deploying the airbag door and the lock cover portion, respectively. An excellent effect that it can be secured is obtained.

  According to the knee-attached airbag device with the column according to claim 3, an excellent effect that the shock absorbing stroke of the steering column can be secured is obtained by deploying the front cover portion including the lock cover portion. .

  According to the knee-attached airbag device with a column according to the fourth aspect, an excellent effect is obtained that the airbag door and the lock cover portion can be easily deployed when the knee airbag is deployed.

  According to the knee-attached airbag device with the column according to claim 5, there is an excellent effect that the shock absorption stroke of the steering column can be secured by suppressing interference between the instrument panel and the airbag door. can get.

  According to the knee-attached airbag device with the column according to claim 6, an excellent effect is obtained that the shock absorbing stroke of the steering column can be secured by deploying the front door portion including the lock cover portion. .

  According to the knee-attached airbag device with the column according to claim 7, an excellent effect that the shock absorbing stroke of the steering column can be ensured by the deformation of the fragile portion provided on the side wall portion of the column cover. can get.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
In FIG. 1, a knee-attached airbag device 10 according to the present embodiment has a knee airbag module 14 that is fixed to the lower side of a steering column 12 and a separate structure from the knee airbag module 14. And a column cover 16.

  First, a configuration example of the steering column 12 will be briefly described. The steering column 12 is a part of a steering mechanism for a small vehicle, for example, and includes a steering main shaft 18 disposed at the shaft core portion, a column tube 22 that covers the steering main shaft 18 and is supported by the vehicle body, and a telescopic mechanism. (Not shown). A steering wheel 24 is fixed to the rear end portion of the steering main shaft 18 using a lock nut (not shown).

  In FIG. 1, the column tube 22 has an outer tube 26 that is a fixed side portion when the steering column 12 contracts when a load of a predetermined value or more is input, and an inner tube (not shown) that is a movable side portion. ing. When the steering main shaft 18 and the column tube 22 are adjusted by a telescopic mechanism and a load greater than or equal to a predetermined value acts on the steering main shaft 18 from the steering wheel 24 side in the axial direction, the shaft is within a predetermined stroke range. It is possible to contract in the direction. Specifically, the steering main shaft 18 and the inner tube that are the movable side portions are configured to stroke (axially move) relative to the outer tube 26 that is the fixed side portion.

  A so-called combination switch 28 is attached to the vicinity of the rear end of the column tube 22, for example, an inner tube. The combination switch 28 is arranged in a state where it protrudes from, for example, both sides of the main body portion 34 and penetrates the through hole 32 of the column cover 16 on the outer peripheral portion near the rear end portion of the inner tube. And a pair of left and right operation levers (not shown). Note that the configuration of the steering column 12 and the combination switch 28 is not limited to the above configuration and the illustrated example.

  The outer tube 26 of the column tube 22 is provided with a lock device 36 that protrudes to one side in the vehicle width direction, for example, to the right side in the vehicle width direction. The lock device 36 is combined with, for example, a key cylinder 58 and an ignition switch (not shown), and is fastened and fixed to the outer tube 26 using, for example, an annular mounting portion 38 (see also FIG. 8B). ).

  Further, the key cylinder 58 in the lock device 36 is disposed at an angle close to parallel to the axial direction of the steering column 12 as compared with a general key cylinder (not shown) extending obliquely downward from the steering column 12. For this reason, as shown in FIG. 8B, the key insertion part 42 of the locking device 36 is in a state of facing substantially rearward of the vehicle. This is because, in a small car, in order to secure a vehicle interior space, the amount of protrusion of the steering column 12 from the instrument panel 92 (see FIG. 7) is limited, and the key cylinder is installed at a general angle. This is because it is difficult to expose the key insertion part 42 to the occupant side. The locking device 36 can lock the rotation of the steering main shaft 18 by engaging a pin or the like (not shown) with the steering main shaft 18 when a predetermined key operation is performed. Yes.

  Next, the knee airbag module 14 is fixed to the vehicle lower side of the steering column 12, and a knee airbag 44 that can be inflated and deployed to the vehicle compartment side by receiving gas supply is folded and stored. Specifically, the knee airbag module 14 houses a folded knee airbag 44 and an inflator 48 capable of supplying inflation gas to the knee airbag 44 in a module case 46. It is configured. A plurality of stud bolts 52 are erected on the inflator 48, and the stud bolts 52 penetrate the module case 46 and project outside.

  On the other hand, the outer tube 26 in the column tube 22 is provided with a mounting bracket 54 for fixing the knee airbag 44 to the outer tube 26. The knee airbag module 14 is fixed to the lower side of the outer tube 26 by inserting a stud bolt 52 into the mounting bracket 54 and fastening a nut 56 to the stud bolt 52. That is, the knee airbag module 14 is fixed not to the column cover 16 side but to the steering column 12 side.

  The inflator 48 is accommodated in the knee airbag 44, for example, and is disposed along the direction orthogonal to the axial direction of the steering column 12, for example, at the vehicle rear end in the module case 46. The inflator 48 is configured to operate in response to an operating current from an airbag ECU (not shown). The airbag ECU generates a frontal collision based on a signal from a front collision sensor (none of which is shown), for example. When it is determined, an operating current is supplied to the inflator 48.

  In addition, how to fold knee airbag 44 and arrangement | positioning of the inflator 48 are not restricted to the example shown by FIG.

  Next, the configuration of the column cover 16 will be described. In FIG. 1, the column cover 16 covers the rear end side of the steering column 12 including the knee airbag module 14 and the lock device 36, and is fixed to a movable side portion when the steering column 12 is contracted. It has an airbag door 60 that expands toward the passenger compartment side by inflation pressure.

  Specifically, the column cover 16 is a molded product made of, for example, a synthetic resin, and has a divided structure including, for example, an upper cover 62 on the upper side of the vehicle and a lower cover 64 on the lower side of the vehicle, and the upper cover 62 and the lower cover 64 are connected to each other. It is configured in combination in a cylindrical shape. The column cover 16 is fixed to, for example, an inner tube of the column tube 22 or a combination switch 28 provided on the inner tube.

  As shown in FIG. 2 (A), an opening 66 for passing the steering main shaft 18 (FIG. 1) is provided at the rear end of the column cover 16. On the side of the column cover 16, an overhanging portion 16 </ b> A that protrudes to the right side of the vehicle width is formed so as to cover the locking device 36. A key hole 16C for allowing a key (not shown) to be inserted into and removed from the key cylinder 58 (FIG. 8B) of the locking device 36 is provided on the rear surface 16B of the overhang portion 16A. The key hole 16 </ b> C and the left and right through holes 32 are located at the joint 68 of the upper cover 62 and the lower cover 64, respectively. That is, the upper hole wall of the key hole 16C and the through hole 32 is formed in the upper cover 62, and the lower hole wall is formed in the lower cover 64. When the upper cover 62 and the lower cover 64 are combined in a cylindrical shape, In addition, a key hole 16C and a through hole 32 are formed.

  On the inner surface of the lower cover 64, there is a space between the airbag door 60 and the lock cover portion 64 </ b> C, and a laterally fractured portion 70 extending in the vehicle width direction along the rear edge of the airbag door 60 and the rear edge of the lock cover portion 64 </ b> C. A longitudinal break planned portion 72 extending in the vehicle front-rear direction is set. Here, the lock cover portion 64C in the present embodiment includes at least a part of the overhang portion 16A that covers the lock device 36 in the lower cover 64, and a side wall portion 64R on the vehicle rear side of the overhang portion 16A.

  The longitudinal fracture scheduled portion 72 is also set between the airbag door 60 and the side wall portion 64L of the lower cover 64 located on the opposite side of the lock cover portion 64C in the vehicle width direction. In consideration of the appearance of the column cover 16, the planned horizontal break portion 70 and the vertical break planned portion 72 are formed on the inner surface of the lower cover 64 as, for example, a groove-like thin portion, and are broken by the inflation pressure of the knee airbag 44. The wall thickness is set to do.

  A hinge portion 74 extending in the vehicle width direction is set on the front edge of the airbag door 60 so as to connect the front ends of the longitudinally fractured portions 72 on both sides. The hinge portion 74 is an integral hinge that is integrally formed with the lower cover 64, and extends to the region of the lower cover 64 that is located on the overhanging portion 16A and the side wall portion 64L on the opposite side of the region in the vehicle width direction. ing. In the lower cover 64, the hinge portion 74 is formed on the vehicle front side with respect to the rear surface 16B of the overhang portion 16A. On the other hand, the planned lateral break portion 70 is formed in the lower wall portion 64D and the side wall portions 64R and 64L on the vehicle rear side with respect to the rear surface 16B of the overhang portion 16A in the lower cover 64. The lateral break planned portion 70 and the hinge portion 74 extend to a joint 68 between the upper cover 62 and the lower cover 64, for example.

  As described above, in the present embodiment, the side portion of the lower cover 64 on the side of the locking device 36 is surrounded by the planned lateral fracture portion 70, the planned longitudinal fracture portion 72, and the hinge portion 74, and reaches the joint 68 with the upper cover 62. The area is a lock cover portion 64C. Note that the lock cover portion 64C does not have to be the entire portion of the column cover 16 that covers the lock device 36 (the overhang portion 16A), and may include at least a portion of the portion that covers the lock device 36. However, the lock cover portion 64 </ b> C preferably includes a portion that covers the key insertion portion 42 located at the rear end portion of the lock device 36. This is because interference between the column cover 16 and the lock device 36 can be more efficiently suppressed when the steering column 12 (FIG. 1) contracts due to shock absorption.

  The airbag door 60 is configured to be deployed below the vehicle around the hinge portion 74 by breaking the laterally fractured scheduled portion 70 and the longitudinally fractured scheduled portion 72 when the knee airbag 44 (FIG. 1) is deployed. ing. At this time, the lock cover portion 64C is configured to expand to the right in the vehicle width direction with the hinge portion 74 as the center, and to be detached from the normal position. Further, the side wall portion 64L is configured to expand to the left in the vehicle width direction with the hinge portion 74 as a center.

As shown in FIG. 1, on the inner surface of the lower cover 64, vertical wall portions 76 and 78 for restricting the deployment direction of the knee airbag 44 and urging and inflating the vehicle compartment are provided, for example. And standing up together. Specifically, the vertical wall portion 76 is provided adjacent to the front side of the knee airbag module 14 and the vertical wall portion 78 is provided adjacent to the rear side of the knee airbag module 14. Of the lower wall portion 64 </ b> D of the lower cover 64, a portion between the vertical wall portions 76 and 78 is set to the airbag door 60. As shown in the figure, the lateral break planned portion 70 is formed at the base portion of the vertical wall portion 78 on the vehicle front side, and the hinge portion 74 is formed at the root portion of the vertical wall portion 76 on the vehicle rear side.
(Function)
This embodiment is configured as described above, and the operation thereof will be described below. In FIG. 1, in the column-attached knee airbag device 10 according to the present embodiment, when the airbag ECU determines the occurrence of a frontal collision based on a signal from a front collision sensor (not shown), the airbag ECU activates the inflator 48. A current flows. The inflator 48 operates in response to the operating current and ejects a large amount of gas. By supplying this gas to the knee airbag 44, the knee airbag 44 begins to expand and deploy.

  When the inflation pressure of the knee airbag 44 acts on the lower cover 64 of the column cover 16, the planned lateral breakage 70 and the planned longitudinal breakage 72 set in the lower cover 64 are broken, as shown in FIG. In addition, the airbag door 60 is deployed below the vehicle around the hinge portion 74. At this time, the lock cover portion 64 </ b> C expands to the right in the vehicle width direction with the hinge portion 74 as the center, and is detached from the normal position. Further, at this time, the side wall portion 64L located on the opposite side of the lock cover portion 64C in the vehicle width direction extends to the left in the vehicle width direction with the hinge portion 74 as the center.

  As shown in FIG. 1, vertical wall portions 76 and 78 are provided on the front and rear of the knee airbag module 14 (front and rear of the airbag door 60), so that the knee airbag 44 is mounted on the vehicle in the column cover 16. It does not expand in the front-rear direction. Specifically, the deployment of the knee airbag 44 toward the vehicle front side in the column cover 16 is regulated by the vertical wall portion 76, and the deployment to the rear side of the collage vehicle is regulated by the vertical wall portion 78. As a result, the inflation and deployment of the knee airbag 44 toward the passenger compartment is promoted.

  In this manner, the knee airbag 44 is inflated and deployed toward the passenger compartment through the opening 80 formed by the deployment of the airbag door 60, the lock cover portion 64C, and the side wall portion 64L. By deploying the lock cover portion 64C and the side wall portion 64L in addition to the airbag door 60, the knee airbag 44 can be quickly deployed not only below the vehicle but also on both sides of the column cover 16 in the vehicle width direction. It is possible to restrain the occupant's knee (not shown) efficiently.

  On the other hand, in FIG. 1, when a load of a predetermined value or more acts on the front side in the axial direction with respect to the steering main shaft 18 from the steering wheel 24 side, the steering column 12 contracts to absorb the impact. At this time, the column cover 16 covering the rear end side of the steering column 12 is a fixed side portion of the steering column 12 and the outer tube 26 to which the lock device 36 is fixed together with the inner tube and the combination switch 28 which are movable side portions. On the other hand, a stroke (moving in the axial direction) is made relatively forward of the vehicle.

  At this time, as described above, the lock cover portion 64C of the column cover 16 is detached from the normal position, and the volume of the column cover 16 remaining in the vicinity of the key insertion portion 42 of the lock device 36 is reduced. The strength of the column cover 16 is reduced compared to the normal case. Thereby, even if the interference between the column cover 16 and the lock device 36 occurs, the interference can be suppressed by the deformation of the column cover 16 easily.

Thus, in the column-attached knee airbag device 10 according to the present embodiment, when the knee airbag 44 is deployed, the laterally fractured scheduled portion 70 and the longitudinally fractured scheduled portion 72 are broken, and the airbag door 60, the lock cover portion 64C, and By deploying the side wall portions 64L, the shock absorbing stroke of the steering column 12 can be secured.
[Second Embodiment]
3 (A), in the column-attached knee airbag device 20 according to the present embodiment, the lower cover 64 of the column cover 16 has a rear cover portion 64B positioned on the vehicle rear side and a lock cover positioned on the vehicle front side. It is set as the division structure which has 64 A of front cover parts comprised including the part 64C.

  The position of the joint 82 between the front cover part 64A and the rear cover part 64B corresponds to, for example, the position of the lateral break planned part 70 in the first embodiment. When the knee airbag 44 (FIG. 1) is deployed, the front cover portion 64A is pivoted downward, for example, around a hinge portion 84 provided at an end portion of the seam 68 on the vehicle front side. It can be expanded to the side.

  The lock cover portion 64C in the present embodiment includes, for example, the entire region of the front cover portion 64A located in the overhang portion 16A of the column cover 16, and a side wall portion 64R on the rear side of the overhang portion 16A. The lower wall portion 64D of the lock cover portion 64C in the present embodiment corresponds to the airbag door 60.

Since other parts are the same as those in the first embodiment, the same parts are denoted by the same reference numerals in the drawings, and the description thereof is omitted. The configurations of the steering column 12 and the knee airbag module 14 are the same as those in the first embodiment (FIG. 1).
(Function)
This embodiment is configured as described above, and the operation thereof will be described below. The operation until the knee airbag 44 (FIG. 1) starts to inflate and deploy is the same as in the first embodiment. 3B, in the column-attached knee airbag device 20 according to the present embodiment, when the inflation pressure of the knee airbag 44 acts on the lower cover 64 of the column cover 16, the lock cover portion 64C of the lower cover 64 is included. For example, the front cover portion 64 </ b> A is rotated downward in the vehicle centering on a hinge portion 84 provided at an end portion on the vehicle front side of the joint 68, so that the front cover portion 64 </ b> A is developed toward the vehicle compartment side. Accordingly, the lower wall portion 64D corresponding to the airbag door 60, the lock cover portion 64C, and the side wall portion 64L located on the opposite side of the lock cover portion 64C in the vehicle width direction are detached from the normal position.

  The knee airbag 44 is inflated and deployed toward the vehicle compartment through an opening 80 formed by the deployment of the front cover portion 64A. By deploying the front cover portion 64A as described above, the knee airbag 44 can be quickly deployed not only on the vehicle lower side but also on both sides in the vehicle width direction of the column cover 16, so that the knee portion (see FIG. (Not shown) can be efficiently restrained.

  On the other hand, as in the first embodiment shown in FIG. 1, when a load of a predetermined value or more acts on the front side in the axial direction with respect to the steering main shaft 18 from the steering wheel 24 side, the steering column 12 Shrink. At this time, as described above, the lock cover portion 64C of the column cover 16 is detached from the normal position when the front cover portion 64A is fully deployed, and remains in the vicinity of the key insertion portion 42 of the lock device 36. Since the volume of the column cover 16 is reduced, the strength of the column cover 16 is reduced as compared with the normal case. Thereby, even if the interference between the column cover 16 and the lock device 36 occurs, the interference can be suppressed by the deformation of the column cover 16 easily.

  Thus, in the knee-attached airbag device 20 according to the present embodiment, the front cover portion 64A including the lock cover portion 64C is deployed, so that the shock absorbing stroke of the steering column 12 can be ensured.

In the present embodiment, the front cover portion 64A of the lower cover 64 is deployed so as to rotate around the hinge portion 84 provided at the end portion of the joint 68 on the vehicle front side. The method of deploying the front cover portion 64A is not limited to this, and the front cover portion 64A may be configured to be separated downward from the vehicle as a whole.
[Third Embodiment]
4A, in the column-attached knee airbag device 30 according to the present embodiment, the lower cover 64 of the column cover 16 has a rear cover portion 64B located on the vehicle rear side and a lock cover located on the vehicle front side. A divided structure having a front cover portion 64A including the portion 64C is provided. Cuts 86 extending in the vehicle front-rear direction are set at corners on both sides in the vehicle width direction at the rear end portion of the front cover portion 64A. The cut 86 is configured as, for example, a continuous or intermittent slit.

  The lock cover portion 64C in the present embodiment has a joint 82, a cut 86, and a hinge portion 74 between the front cover portion 64A and the rear cover portion 64B on the side of the lower cover 64 on the side of the lock device 36 (FIG. 4B). And is set in a region reaching the joint 68 of the upper cover 62 and the lower cover 64. The lock cover portion 64C also includes a side wall portion 64R behind the overhang portion 16A.

Since other parts are the same as those in the first embodiment or the second embodiment, the same parts are denoted by the same reference numerals and the description thereof is omitted. The configurations of the steering column 12 and the knee airbag module 14 are the same as those in the first embodiment (FIG. 1).
(Function)
This embodiment is configured as described above, and the operation thereof will be described below. The operation until the knee airbag 44 (FIG. 1) starts to inflate and deploy is the same as in the first embodiment. In FIG. 4B, in the column-attached knee airbag device 30 according to the present embodiment, cuts 86 extending in the vehicle front-rear direction are set at corners on both sides in the vehicle width direction at the rear end portion of the front cover portion 64A. Therefore, when the inflation pressure of the knee airbag 44 acts on the lower cover 64 of the column cover 16, the lower wall portion 64 </ b> D located between the cuts 86 in the lower cover 64 becomes the airbag door 60 and the hinge portion 74 is centered. The vehicle is deployed downward. Further, at this time, the lock cover portion 64C on the vehicle upper side from the cut 86 expands to the right in the vehicle width direction with the hinge portion 74 as the center, and is detached from the normal position. Further, at this time, the side wall portion 64L opposite to the lock cover portion 64C in the vehicle width direction expands to the left in the vehicle width direction with the hinge portion 74 as the center. By setting the cut 86 in the lower cover 64 in this manner, the airbag door 60, the lock cover portion 64C, and the side wall portion 64L can be easily deployed when the knee airbag 44 is deployed.

  The knee airbag 44 is inflated and deployed toward the passenger compartment through the opening 80 formed by the deployment of the airbag door 60, the lock cover portion 64C, and the side wall portion 64L. By deploying the front cover portion 64A as described above, the knee airbag 44 can be quickly deployed not only on the vehicle lower side but also on both sides in the vehicle width direction of the column cover 16, so that the knee portion (see FIG. (Not shown) can be efficiently restrained.

  On the other hand, as in the first embodiment shown in FIG. 1, when a load of a predetermined value or more acts on the front side in the axial direction with respect to the steering main shaft 18 from the steering wheel 24 side, the steering column 12 Shrink. At this time, as described above, the lock cover portion 64C of the column cover 16 is detached from the normal position, and the volume of the column cover 16 remaining in the vicinity of the key insertion portion 42 of the lock device 36 is reduced. The strength of the column cover 16 is reduced compared to the normal case. Thereby, even if the interference between the column cover 16 and the lock device 36 occurs, the interference can be suppressed by the deformation of the column cover 16 easily.

In this manner, in the column-attached knee airbag device 30 according to the present embodiment, by setting the cut 86 in the front cover portion 64A of the lower cover 64, the airbag door 60 and the lock cover portion 64C when the knee airbag 44 is deployed. And the side wall part 64L can be easily expand | deployed. This also ensures the shock absorbing stroke of the steering column 12.
[Fourth Embodiment]
5A, in the column-attached knee airbag device 40 according to the present embodiment, the airbag door 60 is assembled as a separate body below the lower cover 64 of the column cover 16. The position of the rear edge of the airbag door 60 corresponds to, for example, the position of the planned lateral fracture portion 70, and the position of the front edge of the airbag door 60 corresponds to, for example, the position of the hinge portion 74. Further, the position of the side edge of the airbag door 60 corresponds to the position of the longitudinally fractured portion 72 (FIG. 2A) in the first embodiment, for example. In other words, the position of the side edge of the airbag door 60 is set at the corners on both sides in the vehicle width direction at the rear end portion of the lower cover 64.

  The airbag door 60 is assembled so as to be flush with the lower wall portion 64D of the lower cover 64 when viewed from the vehicle lower side of the column cover 16. The airbag door 60 is locked to the lower cover 64 by a locking claw 96, for example. 6A or 6B, the airbag door 60 is connected to the lower cover 64 of the column cover 16 via an extendable hinge 88. As shown in FIG. The airbag door 60 is configured to be separated from the lower cover 64 of the column cover 16 by the inflation pressure of the knee airbag 44 and to be deployed to the vehicle compartment side while being supported by a hinge 88.

  As shown in FIG. 6A, as the hinge 88, for example, a mesh hinge having extensibility can be used. In this example, the hinge 88 is configured to have a slight extra length, and the extra length is normally folded on the upper surface side of the airbag door 60. The hinge 88 is bonded to, for example, the front edge of the airbag door 60 and the lower portion of the vertical wall portion 76 in the lower cover 64.

  Further, as shown in FIG. 6B, as the hinge 88, for example, an integral hinge can be used. In this example, the hinge 88 is integrally formed on the upper surface of the airbag door 60, for example, and is configured to have a surplus length portion for extension. The surplus length portion is formed on the upper surface side of the airbag door 60. For example, it is in a folded state. The end portion 90 of the hinge 88 is bonded or welded, for example, to the upper surface side of the lower wall portion 64D of the lower cover 64, whereby the front edge of the airbag door 60 is connected to the lower cover 64.

  In addition, about the hinge 88, it is good also as a structure which does not provide a surplus length part using the material which has comparatively big extensibility. On the contrary, the extra length portion may be provided while using a material having relatively low extensibility or a non-extensible material.

Since other parts are the same as those in the first embodiment, the same parts are denoted by the same reference numerals in the drawings, and the description thereof is omitted. The configurations of the steering column 12 and the knee airbag module 14 are the same as those in the first embodiment (FIG. 1).
(Function)
This embodiment is configured as described above, and the operation thereof will be described below. The operation until the knee airbag 44 (FIG. 1) starts to inflate and deploy is the same as in the first embodiment. In FIG. 5B, in the column-attached knee airbag device 40 according to the present embodiment, when the inflation pressure of the knee airbag 44 acts on the lower cover 64 of the column cover 16, it is assembled separately at the lower part of the lower cover 64. The airbag door 60 is detached from the lower cover 64 and is deployed to the vehicle compartment side while being supported by the hinge 88.

  When the inflation pressure of the knee airbag 44 acts on the lower cover 64 of the column cover 16, the lock cover portion 64 </ b> C expands to the right in the vehicle width direction with the hinge portion 74 as the center, and is released from the normal position. Further, at this time, the side wall portion 64L located on the opposite side of the lock cover portion 64C in the vehicle width direction extends to the left in the vehicle width direction with the hinge portion 74 as the center.

  The knee airbag 44 is inflated and deployed toward the passenger compartment through the opening 80 formed by the deployment of the airbag door 60, the lock cover portion 64C, and the side wall portion 64L. As described above, in addition to the airbag door 60, the lock cover portion 64C and the side wall portion 64L are deployed, so that the knee airbag 44 is not only on the vehicle lower side but also on both sides of the column cover 16 in the vehicle width direction. The occupant's knee (not shown) can be efficiently restrained.

  Here, in FIG. 7A, the deployment of the airbag door 60 will be described in more detail. When the inflation pressure of the knee airbag 44 acts on the airbag door 60, the locking claw 96 of the airbag door 60 causes the lower cover 64 to move. The airbag door 60 is released from the locked state, and the airbag door 60 is detached from the lower cover 64. Since the front edge of the airbag door 60 is connected to the lower cover 64 by a hinge 88, the airbag door 60 is deployed to the vehicle compartment 94 side (below the vehicle) while being supported by the hinge 88.

  On the other hand, as shown in FIG. 7B, when a load of a predetermined value or more acts on the front side in the axial direction with respect to the steering main shaft 18 from the steering wheel 24 side, the steering column 12 contracts to absorb the impact. . At this time, the column cover 16 strokes relative to the movable side portion of the steering column 12 relative to the fixed side portion of the steering column 12 to which the locking device 36 is fixed, and the airbag door 60 is moved to the vehicle compartment 94 side. It leaves in the instrument panel 92 while leaving.

  At this time, the hinge 88 connecting the airbag door 60 and the lower cover 64 of the column cover 16 extends, so that interference between the airbag door 60 and the instrument panel 92 can be suppressed. As a result, even if the airbag door 60 remains on the vehicle compartment 94 side, the steering column 12 can smoothly stroke. For this reason, in the column-attached knee airbag device 40 according to the present embodiment, the shock absorbing stroke of the steering column 12 can be ensured by suppressing the interference between the instrument panel 92 and the airbag door 60.

Similarly to the first embodiment, the shock absorbing stroke of the steering column 12 can be secured by suppressing interference between the column cover 16 and the lock device 36.
[Fifth Embodiment]
8A, in the column-attached knee airbag device 50 according to the present embodiment, the airbag door 60 includes a front door portion 60F and a rear door portion 60R. The front door portion 60F and the rear door portion 60R are integrally formed with the lower cover 64.

  The front door portion 60F is formed so as to include a lock cover portion 64C so as to go from a lower wall portion 64D of the lower cover 64 in the column cover 16 to a side wall portion 64R on the right side of the vehicle and a side wall portion (not shown) on the left side of the vehicle. When the knee airbag 44 is deployed, the knee airbag 44 is configured to be deployable in the direction of arrow F around the hinge portion 74 on the front side of the vehicle. The front door portion 60F has a U-shaped cross section as a whole.

  The rear door portion 60R is provided adjacent to the vehicle rear side of the front door portion 60F, and is configured to be deployable in the arrow R direction around the hinge portion 98 on the vehicle rear side when the knee airbag 44 is deployed. ing. Similarly to the front door portion 60F, the rear door portion 60R is formed to wrap around from the lower wall portion 64D to the side wall portion 64R on the right side of the vehicle and the side wall portion (not shown) on the left side of the vehicle. It has become.

  The lock cover part 64C in the present embodiment includes at least a part of the overhang part 16A that covers the lock device 36 and a part of the side wall part 64R on the vehicle rear side of the overhang part 16A. Supplementally, the lock cover portion 64C is set to partially overlap the key cylinder 58 of the lock device 36 in the vehicle width direction. Note that the range of the front door portion 60F may be expanded upward of the vehicle up to the joint 68 of the upper cover 62 and the lower cover 64.

  The distance between the hinge portion 74 on the vehicle front side and the hinge portion 98 on the vehicle rear side is set in accordance with the size of the knee airbag module 14 (see FIG. 1). In the lower cover 64, a planned fracture portion 100 is set along the contours of the front door portion 60F and the rear door portion 60R excluding the hinge portions 74 and 98. The planned fracture portion 100 is configured, for example, as a groove-shaped thin portion on the inner surface of the lower cover 64, and is set to have a thickness so as to be broken by the inflation pressure of the knee airbag 44 (see FIG. 1).

  In the column cover 16, a weak portion 102 that is vulnerable to an axial load of the steering column 12 is provided on a side wall portion of the column device 16 positioned behind the lock device 36. In FIG. 8 (B), this weak part 102 is comprised as a thin part of a side wall part. In the vehicle longitudinal direction, the fragile portion 102 is formed, for example, in a region from the rear surface 16B of the column cover 16 to the vicinity of the rear end of the rear door portion 60R. Moreover, the weak part 102 is formed in the range larger than the diameter of the key cylinder 58 of the locking device 36, for example in the vehicle up-down direction. Further, the fragile portion 102 is formed from the upper cover 62 to the lower cover 64 in the column cover 16, and a part thereof reaches, for example, the region of the airbag door 60.

  In addition, the weak part 102 is not restricted to a thin part, For example, the groove | channel extended in the vehicle up-down direction may be arranged in multiple numbers in the vehicle front-back direction. In other words, the fragile portion 102 may be fragile to the axial load of the steering column 12 and may be configured to be easily deformable when interference with the lock device 36 occurs.

Since other parts are the same as those in the first embodiment, the same parts are denoted by the same reference numerals in the drawings, and the description thereof is omitted. The configurations of the steering column 12 and the knee airbag module 14 are the same as those in the first embodiment (FIG. 1).
(Function)
This embodiment is configured as described above, and the operation thereof will be described below. The operation until the knee airbag 44 (FIG. 1) starts to inflate and deploy is the same as in the first embodiment. In FIG. 8A, in the column-attached knee airbag device 50 according to the present embodiment, when the inflation pressure of the knee airbag 44 acts on the lower cover 64 of the column cover 16, the planned breakage portion 100 is broken and the airbag door is broken. The front door portion 60F in 60 extends in the direction of arrow F around the hinge portion 74 on the front side of the vehicle, and the rear door portion 60R in the airbag door 60 has an arrow about the hinge portion 98 on the rear side of the vehicle. Expand in the R direction.

  Since the front door portion 60F is formed to wrap around from the lower wall portion 64D of the lower cover 64 in the column cover 16 to the side wall portion 64R so as to include the lock cover portion 64C, the front door portion 60F is expanded, The lock cover portion 64C is detached from the normal position. In the present embodiment, by providing the front door portion 60F and the rear door portion 60R as the airbag door 60, an opening (not shown) for inflating the knee airbag can be efficiently formed.

  The knee airbag 44 is inflated and deployed toward the passenger compartment through this opening. By deploying the front door portion 60F and the rear door portion 60R as described above, the knee airbag 44 can be quickly deployed not only below the vehicle but also on both sides in the vehicle width direction of the column cover 16, It is possible to efficiently restrain an occupant's knee (not shown).

  On the other hand, when the steering column 12 contracts to absorb the shock, the column cover 16 moves relative to the fixed side portion of the steering column 12 to which the locking device 36 is fixed together with the movable side portion of the steering column 12. Stroke to. Here, as described above, the lock cover portion 64C of the column cover 16 is detached from the normal position when the front door portion 60F is deployed, and remains in the vicinity of the key insertion portion 42 of the lock device 36. Since the volume of the column cover 16 is reduced, the strength of the column cover 16 is reduced as compared with the normal case.

  In addition to this, a weak portion 102 that is vulnerable to the axial load of the steering column 12 is provided on the side wall portion of the column cover 16 that is located behind the lock device 36 in the vehicle. Even if it interferes with the locking device 36, the weakened portion 102 is easily deformed, so that the interference can be further suppressed.

  As described above, in the column-attached knee airbag device 50 according to the present embodiment, the front door portion 60F including the lock cover portion 64C is deployed, and the fragile portion 102 provided on the side wall portion of the column cover 16 is deformed. Thus, the shock absorbing stroke of the steering column 12 can be secured.

  Note that the fragile portion 102 can be applied to the first embodiment, the third embodiment, and the fourth embodiment. Conversely, in the present embodiment, a configuration in which the fragile portion 102 is not provided is also possible.

1 and 2 relate to a first embodiment, and FIG. 1 is a cross-sectional view showing a column-attached knee airbag device. (A) It is a perspective view which shows the column cover in the normal time. (B) It is a perspective view which shows the state which the airbag door, the lock cover part, and the side wall part expand | deployed. (A) It is a perspective view which shows the column cover in the normal time in the column-attached knee airbag device according to the second embodiment. (B) It is a perspective view which shows the state which the lower cover expand | deployed to the vehicle interior side by rotating below a vehicle centering on a hinge part. (A) It is a perspective view which shows the column cover in the normal time in the column-attached knee airbag device according to the third embodiment. (B) It is a perspective view which shows the state which the airbag door, the lock cover part, and the side wall part of the vehicle left side expand | deployed. (A) FIGS. 5 to 7 relate to a fourth embodiment, and FIG. 5 (A) is a perspective view showing a column cover and an airbag door in a normal state. (B) It is a perspective view which shows the state which the airbag door, the lock cover part, and the side wall part of the vehicle left side expand | deployed. (A) It is a 6A-6A arrow expanded sectional view in Drawing 5 (A) showing a mesh hinge which is an example of a hinge. (B) 6B-6B arrow expanded sectional view in FIG. 5 (A) which shows the integral hinge which is an example of a hinge. (A) It is sectional drawing which shows the state which the airbag door is expand | deployed by the inflation pressure of a knee airbag before the shrinkage | contraction of a steering column. (B) It is sectional drawing which shows the state by which the interference with an airbag door and an instrument panel is suppressed by the hinge extending | stretching in the state which the steering column contracted. (A) It is a side view which shows the column-attached knee airbag apparatus which concerns on 5th Embodiment. (B) 8B in FIG. 8 (A) showing a state in which interference between the column cover and the lock device is suppressed by deformation of the weakened portion provided on the side wall portion of the column cover when the steering column is contracted. It is -8B arrow sectional drawing.

Explanation of symbols

10 Knee airbag device with column 12 Steering column 14 Knee airbag module 16 Column cover 18 Steering main shaft (movable side part)
20 Knee airbag device with column 26 Outer tube (fixed side part)
28 Combination switch (movable part)
30 Knee airbag device with column 36 Lock device 40 Knee airbag device with column 44 Knee airbag 50 Knee airbag device with column 60 Airbag door 60F Front door portion 60R Rear door portion 62 Upper cover 64 Lower cover 64A Front cover portion 64B Rear cover part 64C Lock cover part 64D Lower wall part 64L Side wall part 64R Side wall part 70 Lateral fracture part 72 Longitudinal fracture part 74 Hinge part on the front side of the vehicle 86 Cut 88 Hinge 94 Car compartment 98 Hinge part on the rear side of the vehicle 102 Vulnerable part

Claims (7)

The steering column is fixed to the lower side of the steering column, which is configured to be retractable by a load input of a predetermined value or more, and the locking device is fixed to the fixed side portion at the time of contraction. A knee airbag module in which the knee airbag is folded and stored;
Air that covers a rear end side of the steering column including the knee airbag module and the locking device, is fixed to a movable side portion when the steering column is contracted, and is developed toward the vehicle compartment side by the inflation pressure of the knee airbag A column cover having a bag door,
A knee-attached airbag device with a column, wherein a lock cover portion that covers the lock device of the column cover is detached from a normal position when the knee airbag is deployed. In the column cover,
A laterally fractured portion extending in a vehicle width direction along a rear edge of the airbag door and a rear edge of the lock cover portion;
A longitudinally fractured portion extending in the vehicle front-rear direction between the airbag door and the lock cover portion is set,
2. The column mounting knee according to claim 1, wherein when the knee airbag is deployed, the airbag door is deployed downward in the vehicle and the lock cover portion is deployed in the vehicle width direction. Airbag device. The column cover has a divided structure having an upper cover on the vehicle upper side and a lower cover on the vehicle lower side,
The lower cover has a split structure including a rear cover portion located on the vehicle rear side and a front cover portion located on the vehicle front side and configured to include the lock cover portion,
The column-attached knee airbag device according to claim 1, wherein the front cover portion is configured to be deployable toward a passenger compartment when the knee airbag is deployed.   The column-attached knee airbag device according to claim 3, wherein a cut extending in the vehicle front-rear direction is set at corners on both sides in the vehicle width direction at a rear end portion of the front cover portion.   The airbag door is separately assembled to the lower portion of the column cover, and is connected to the column cover via an extendable hinge. The airbag door is detached from the column cover by the inflation pressure of the knee airbag, and The column-attached knee airbag device according to claim 1, wherein the knee-attached airbag device is configured to be deployable toward the passenger compartment while being supported by a hinge. The airbag door is
A front door portion formed around the side wall portion of the column cover so as to include the lock cover portion, and deployable around a hinge portion on the vehicle front side when the knee airbag is deployed;
A rear door portion provided adjacent to the vehicle rear side of the front door portion and capable of being deployed around a hinge portion on the vehicle rear side when the knee airbag is deployed. The knee-attached airbag device with a column according to claim 1,   The fragile part which is weak with respect to the load of the axial direction of the said steering column is provided in the side wall part located in the vehicle rear of the said locking device among the said column covers. 7. The knee-attached airbag device with a column according to any one of 6 above.

Images